/*
 *    This program is free software; you can redistribute it and/or modify
 *    it under the terms of the GNU General Public License as published by
 *    the Free Software Foundation; either version 2 of the License, or
 *    (at your option) any later version.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU General Public License for more details.
 *
 *    You should have received a copy of the GNU General Public License
 *    along with this program; if not, write to the Free Software
 *    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

/*
 * RandomizableClusterer.java
 * Copyright (C) 2006 University of Waikato, Hamilton, New Zealand
 *
 */

package weka.clusterers;

import weka.core.Option;
import weka.core.OptionHandler;
import weka.core.Randomizable;
import weka.core.Utils;

import java.util.Enumeration;
import java.util.Vector;

/**
 * Abstract utility class for handling settings common to randomizable
 * clusterers.
 * 
 * @author FracPete (fracpete at waikato dot ac dot nz)
 * @version $Revision: 1.3 $
 */
public abstract class RandomizableClusterer extends AbstractClusterer implements
		OptionHandler, Randomizable {

	/** for serialization */
	private static final long serialVersionUID = -4819590778152242745L;

	/** the default seed value */
	protected int m_SeedDefault = 1;

	/** The random number seed. */
	protected int m_Seed = m_SeedDefault;

	/**
	 * Returns an enumeration describing the available options.
	 * 
	 * @return an enumeration of all the available options.
	 */
	public Enumeration listOptions() {
		Vector result = new Vector();

		result.addElement(new Option("\tRandom number seed.\n" + "\t(default "
				+ m_SeedDefault + ")", "S", 1, "-S <num>"));

		return result.elements();
	}

	/**
	 * Parses a given list of options. Valid options are:
	 * <p>
	 * 
	 * @param options
	 *            the list of options as an array of strings
	 * @throws Exception
	 *             if an option is not supported
	 */
	public void setOptions(String[] options) throws Exception {
		String tmpStr;

		tmpStr = Utils.getOption('S', options);
		if (tmpStr.length() != 0)
			setSeed(Integer.parseInt(tmpStr));
		else
			setSeed(m_SeedDefault);
	}

	/**
	 * Gets the current settings of the classifier.
	 * 
	 * @return an array of strings suitable for passing to setOptions
	 */
	public String[] getOptions() {
		Vector result;

		result = new Vector();

		result.add("-S");
		result.add("" + getSeed());

		return (String[]) result.toArray(new String[result.size()]);
	}

	/**
	 * Returns the tip text for this property
	 * 
	 * @return tip text for this property suitable for displaying in the
	 *         explorer/experimenter gui
	 */
	public String seedTipText() {
		return "The random number seed to be used.";
	}

	/**
	 * Set the seed for random number generation.
	 * 
	 * @param value
	 *            the seed to use
	 */
	public void setSeed(int value) {
		m_Seed = value;
	}

	/**
	 * Gets the seed for the random number generations
	 * 
	 * @return the seed for the random number generation
	 */
	public int getSeed() {
		return m_Seed;
	}
}
